Defense

Saul · Post by **Saul** » Mon Apr 30, 2018 7:02 pm

Bark beetle larvae's very end - why this place needs a such defense ?

Nikon D7200, Mitutoyo 10x/Asahi Super Takumar 105mm 2.8, not SMC version (thanks Steve B. (Beatsy), great combination), stack/stitch, around 250 photos, DMap/PMax, FO lights

Bigger:
https://c1.staticflickr.com/1/967/26947 ... acab_o.jpg

rjlittlefield · Post by **rjlittlefield** » Mon Apr 30, 2018 9:46 pm

Maybe not defense. Could instead be how the larva pushes against the sides of its tunnel, so the mandibles at the other end of the larva can chew more wood. Those long hairs on either side look like sensory setae -- just the thing to monitor the sides of the tunnel.

Great image in any case.

--Rik

razashaikh · Post by **razashaikh** » Mon Apr 30, 2018 10:20 pm

Great observation.

Saul · Post by **Saul** » Mon Apr 30, 2018 10:22 pm

Thanks, Rik !
Interesting explanation. And these bottom "teeth" - somehow they are matching anal opening - what purpose they are serving ?
And area between mandibles - looks like some kind of sensors ?

rjlittlefield · Post by **rjlittlefield** » Mon Apr 30, 2018 11:19 pm

My comment about pushing was basically an extension of Troel's suggestion, at http://www.photomacrography.net/forum/v ... 463#226463 .

As for the bottom "teeth", I have no idea! Likewise for most of the rest of the stuff.

"area between mandibles", I don't think we can see that here. This looks like the tail end with the "urogomphi" -- mandibles would be on the other end.

--Rik

Beatsy · Post by **Beatsy** » Mon Apr 30, 2018 11:43 pm

Impressive set of pickled onion stabbers! Impressive pic too - very nice.

Lou Jost · Post by **Lou Jost** » Tue May 01, 2018 6:18 am

Also, a lot of things that live in tunnels need to retract themselves into it sometimes, so it may be for grasping and pulling more than for pushing. Or, if the larva is head-down in the tunnel, it may need to defend its rear against predators and parasitoids.

Saul · Post by **Saul** » Tue May 01, 2018 7:57 am

rjlittlefield wrote:..."area between mandibles", I don't think we can see that here. This looks like the tail end with the "urogomphi" -- mandibles would be on the other end. --Rik

Sorry, my mistake, I meant this area:

rjlittlefield · Post by **rjlittlefield** » Tue May 01, 2018 8:12 am

Lou Jost wrote:it may be for grasping and pulling more than for pushing.

My understanding is that these urogomphi are a single rigid unit, not an articulated pair that can grasp or pinch.

Saul, no idea about those serrations.

--Rik

JH · Post by JH » Tue May 01, 2018 10:40 am

Saul, Nice pictures - I really like the light!
I guess this is with your own LED light construction.
Best regards
Jörgen Hellberg

Saul · Post by **Saul** » Tue May 01, 2018 10:53 am

JH wrote:Saul, Nice pictures - I really like the light!
I guess this is with your own LED light construction.
Best regards
Jörgen Hellberg

Thanks, Jörgen !

Yes, it is done with DIY FO LED lights and timer-delay module

Lou Jost · Post by **Lou Jost** » Tue May 01, 2018 11:24 am

Rik, yes, now I see that there are no real sutures between them.